1. Field
The following description relates to a system and a device for transferring power without a cable.
2. Description of Related Art
Electromagnetic wireless power transfer systems are classified into radiative systems and non-radiative systems. Radiative power transfer systems are based on narrow-beam transmitters, and utilize electromagnetic radiation in a far field. Non-radiative power transfer systems are based on electromagnetic induction, and utilize non-radiation in a near field.
Interest in non-radiative power transfer systems has grown significantly after a resonance power transfer scheme was proposed. Nearly all known resonance-based devices transferring wireless power are based on electromagnetic resonator structures. Resonator structures used for resonance power transfer systems may also be used in non-resonance systems, for example, radiative systems.
A drawback of electromagnetic resonator structures includes the complicated process of manufacturing a small-sized, sensitive electromagnetic resonator with a high quality factor (Q-factor Q). Another drawback includes complications with production of an electromagnetic resonator including a high Q-factor but a low resonance frequency. To increase an efficiency of a power transfer process, it is desirable to make a Q-factor of an electromagnetic resonator as high as possible.